Using the Excel file containing the S&P 500 index from the end of 1990 to the end of June 2022 below, calculate the historical daily volatility during the period from 1991 to 2020, and calculate the annual volatility assuming that daily movements in prices are independent of each other. Based on the results, explain briefly how usual/unusual was the year 2021.

The daily volatility from 1991 to 2020=737.868

the annual volatility=11713.2878

The daily volatility of 2021=286.8729

the annual volatility of 2021=4553.96